Negligible future warming from: CO2 – CH4 – N2O

From edmhdotme

Ed Hoskins

As at its current concentration atmospheric CO2 at 420 ppmv is already more than 85% saturated,  its Global warming potential is almost entirely exhausted.

All attempts by Mankind to limit further CO2 emissions will have no further significant controlling effect on Global temperature.

Further actions by the Western minority of Man-kind to protect against a supposed Global Overheating Catastrophe from CO2 emissions are pointless.

Introduction

A cogent case can be made that all future Man-made emissions of the minor Greenhouse gasses are:

• irrelevant to the future of the World’s climate.
• cannot pose any real overheating problem in future.
• certainly not imposing any existential disaster for Mankind.
• this is fortunate as the developing world, 80+% of the global population, is taking no notice of the alarm about CO2 emissions causing Global Overheating that is now fashionable in the West.

instead

• atmospheric CO2, even at its current historically low level, is making a huge and absolutely essential contribution  to the well being of Planet Earth via it support of photosynthesis and healthy plant growth.

These analyses, they show that:

• as at the current CO2 level of 420ppmv the effectiveness of CO2 as a warming agent is now almost fully saturated.
• there is no possibility of any overheating Climate emergency, nor any future temperature Catastrophe caused by increasing Man-made CO2 emissions from burning of Fossil Fuels.
• there is now no rational imperative for Western economies to eliminate CO2 or other Greenhouse Gas emissions from Methane and Nitrous Oxide by implementing their Net Zero policies.
• there is no reason whatsoever to try to control Methane or Nitrous Oxide emissions to avoid Global Warming.  The inherent chemistry of these powerful Greenhouse gasses means that any extra emissions are always be rapidly purged in the Earth’s Oxygen rich atmosphere, leaving only small residues in the atmosphere, only measurable in parts per billion, resulting in a minor and static effect on Global temperature.

Although studiously ignored by Climate Alarmist thinking, the Water in the atmosphere either as Water Vapour or as Clouds is the main Greenhouse Gas, accounting for roughly 85% – 95% of the total warming effect or about ~30°C of the estimated ~+33°C Greenhouse effect.  The Greenhouse effect of Water in the atmosphere varies according to latitude, local climate and local humidity roughly within that range. Mankind has no influence on the amount or distribution of water in the atmosphere. 

The water-based Greenhouse effect of ~+30°C is essential to the continuance of all life on Earth. 

The Water in the atmosphere maintains the habitability of the planet and thus supports all Life-on-Earth.

This note and its illustrations show the context, proportionality and scale of the temperature effects of the minor greenhouse gasses emphasizing their future irrelevance.

Note:  the values shown here are deliberately approximate, as indicated by the symbol “~”. The values here show minimal values for the temperature effect of CO2 and other Greenhouse gasses.  Actual values are more variable according to local climate conditions, humidity, longitude, etc.  Nonetheless, the values are at the right scale and in the right ball park.  

The long-term context of the atmospheric composition and temperature

The diagrams below summarize the evolution of the Earth’s atmosphere over the past 4.6 billion years and show global variations in temperature and CO2 concentration over the more recent the Phanerozoic eon, the last ~600 million years, the period over which the whole of advanced Life-on-Earth has emerged.

Over most of Phanerozoic eon Global temperatures have been substantially higher than at present, (+~ 15°C ).  Global temperatures are now low by comparison.

About 2.5 million years ago the Earth entered an Ice Age, with permanent ice sheets at both poles.  Long cold periods lasting ~1000,000+ years are interspersed by shorter inter-glacial periods of ~10,000+ years. This pattern is established by the mechanics of the Solar System and its Milankovitch cycles.

The more recent temperature pictures show a massive decline that started some 55 million years ago.  And the history of our current Holocene inter-glacial shows that any temperature recovery from the recent little ice age is marginal in comparison with more significant variations even in the recent past.

Over most of the 600 million year Phanerozoic eon Global temperatures have been substantially higher than at present, (+~15°C ).  Global temperatures are now low by comparison.

About 2.5 million years ago the Earth entered an Ice Age, with permanent ice sheets at both poles.  Long cold periods lasting ~100,000+ years are interspersed by shorter inter-glacial periods of ~10,000+ years. This pattern is established by the mechanics of the Solar System and its Milankovitch cycles.

The more recent temperature pictures show a massive decline that started some 55 million years ago.  And the history of our current Holocene inter-glacial shows that any temperature recovery from the little ice age is marginal in comparison with more significant variations even in the recent past.

Our current Holocene inter-glacial is the most recent of those warmer inter-glacial times.

The warmer Holocene epoch of the last ~10,000+ years has been the enabler of the development of Man-kind’s civilizations, from the stone age to computing.

Judging from past inter-glacials after ~10,000 years, our current Holocene period, should be drawing to its close, sometime this century, next century or this millennium.

The ending of the Holocene and the subsequent reversion of the World to real Ice Age conditions will result in a true catastrophe for the World and Humankind.

There is now a real risk that the inexorable Carbon sequestration processes progressing in the world’s oceans will lead to atmospheric CO2 levels falling below the Photosynthetic terminal level of 150ppmv during some future Glaciation.

With the eventual failure of Photosynthesis from lack of atmospheric CO2, all Life-on-Earth will end in some future Glacial period.  There is even a chance that the happenstance of Man-kind’s current activities, adding to CO2 levels by burning fossil fuels may raise the threshold of atmospheric CO2 and thus delay the final steps of the CO2 sequestration process and even prolong the survival of  life on Earth.

For the last 100 million years atmospheric CO2 levels have been reducing progressively.  At the start of our current the Holocene epoch only 20,000 years ago, the CO2 level had fallen to 180ppmv.  This was only 20% above the terminal level for all Life-on-Earth, (Photosynthesis fails below 150ppmv).

With industrialization and the exploitation of Fossil fuels Man-kind has made especially rapid technical advances over the last 200 years.  This has resulted in huge advances in the well-being for the majority of the 8 billion people now sustained by planet Earth.

The radiation physics of atmospheric CO2 by Professor William Happer

This presentation by Professor William Happer provides an explanation of the atmospheric radiation physics shows that the temperature effectiveness of CO2 diminishes logarithmically.  At the current 420pppmv the temperature effect of atmospheric CO2 is ~85% saturated.  Any possible future CO2 temperature effects are well below any of the Alarmist and official predictions that are asserted by the Climate Modelling of the IPCC, (UN Intergovernmental Panel on Climate Change).

Professor Happer’s specialism is the radiation physics of energy transfer in the atmosphere. In the early 1990’s, whilst Director of Energy Research in the U.S. Department of Energy during the George Bush presidency, Professor Happer was responsible for setting up many of the American Climate Research establishments.

Professor Happer explains the atmospheric Radiation Physics involved in this presentation.

Paraphrasing Professor Happer

“The important point here is the red line on this chart.  It shows what would happen if the concentration of CO2 was doubled.  The gap between the black line and the red line shows the extent of the effect of doubling CO2.  So, you can see that doubling CO2 now makes virtually no difference.

On the basis of this minuscule difference, we are supposed to give up our liberties, give up the gasoline engines in our automobiles, give up all the benefits of Western Industrial society and submit to dictatorial Government controls”.

“The message I want you to understand is:

don’t let anyone convince you that is a good bargain:  it is in fact a terrible bargain.”

Alarmist reasoning for their view of a massive temperature increase from Man-made CO2

Climate alarmists, assert via their models that the release of additional “Western” increments of Man-made CO2, greater than 420ppmv, (capable of only causing very small temperature increases), will result in a massive positive temperature feedback from the additional water evaporated into the atmosphere.  Massive positive feedback processes like this are unknown in the earlier natural billion year past records.  Much higher concentrations of atmospheric CO2 have never caused runaway warming.   Such massive positive events would conflict with the Le Chatelier principal with determines that positive feedbacks are very rare and almost unheard of in nature.

Low levels of Carbon Dioxide contribute most to Greenhouse warming

The following diagram uses the US  EPA estimate that the whole CO2 based component of Global warming amounts to ~8.2% of the total Greenhouse effect:  33°C * 8.2%  =  +~2.71°C up to a maximum CO2 level of 1000ppmv.  As the warming effect of CO2 still diminishes logarithmically further increases of the CO2 level have ever less important effects on Global temperature.  In this analysis the increments are ignored beyond 1000 ppmv.

Notes:

• the background of the diagram represents the influence of CO2 on plant viability, from death of plants below 150ppmv shown in black, to verdant green at 1000ppmv on the right.
• the other minor contributors to Global Warming are:
  • the temperature contribution of each 10ppmv tranche of CO2 as Orange columns reducing logarithmically with increasing CO2 concentration:
  • the stable temperature contribution of Methane is shown as pale blue.
  • the stable temperature contribution of Nitrous Oxide is shown as purple.
  • the temperature effect of CO2 up to the current 420ppmv is shown as solid Red.
  • the temperature effect of CO2 beyond 420ppmv is shown as hatched Red.
• the Temperature values of each 10-ppmv CO2 tranche, (shown in Orange), are cumulative to the overall CO2 contribution to Global temperature.
• Logarithmic Diminution of the CO2 Greenhouse temperature effect means that the lowest concentrations of CO2 have already made by far the greatest temperature contribution.
• thus, the characterization of Carbon Dioxide as a pollutant in future:
  • as is asserted in the US EPA “Endangerment Finding”.
  • as is taught throughout Western educational establishments.
  • as had been accepted and promoted by many Western Governments, under the guidance of the UN IPCC, (the UN Intergovernmental Panel on Climate Change).

is a gross misrepresentation of the role of atmospheric CO2.

On the contrary CO2 in the atmosphere is the absolutely essential Gas of Life.

• accordingly, the first 10 ppmv tranche of CO2 contributes ~+0.35°C or ~13% of the total CO2 warming effect.
• a first tranche up to 150 ppmv CO2 maintains the viability of Photosynthesis and is thus is essential for the marginal survival of all Life -on-Earth.
• at 150 ppmv the temperature effect of CO2 amounting to +~1.42°C or 52% of its total warming effect.
• at the start of our current Holocene inter-glacial the CO2 concentration was 180ppmv, a level only 20% above the terminal level for the failure of Photosynthesis.
• the increase of CO2 from 150ppmv to 280ppmv, the pre-industrial CO2 level contributes ~+0.30°C or up to ~63% of the total CO2 warming effect: this increase of CO2 can be attributed to the continuing out-gassing from the warming oceans as the Holocene progressed.
• the more recent increase from 280ppmv to 420ppmv CO2 level is partly attributable to Man-made CO2 emissions.  It contributes ~+0.2°C or up to ~70% of the total CO2 warming effect.
• the total Greenhouse Gas effect including CO2, Methane and Nitrous Oxide contribution to date with at CO2 420 ppmv amounts to +~ 2.45°C or ~90% of the total CO2 warming effect.
• having now reached 420 ppmv the warming effect of CO2 is >85% saturated.  This is well beyond the point where whatever further increase of the concentration of atmospheric CO2 could produce any significant temperature increase.

• ECS, Equilibrium Climate Sensitivity is defined as the temperature effect of a doubling CO2 concentration from the current 420 ppmv onwards to 840 ppmv.
• reaching ECS could now only result in a ~1%+ effect to increase the CO2 temperature ~+0.33°C, well within the range of natural variability.
• the reduction of the warming effect of CO2 beyond ~420 ppmv, can be seen a as the long tail of diminishing orange columns approaching 1000 ppmv.
• thus, the continuing increase in atmospheric CO2 if produced by mankind will have only very marginal temperature effects.
• any further increase in atmospheric CO2 would make a huge contribution to the well being of planet Earth by the further enhancement of Photosynthesis.

CO2 starvation

• even at the present with the value of 420 ppmv, (a level which is considered by Climate Alarmists to be “excessively dangerous for Global overheating”), the Earth is still in a state of CO2 deprivation when compared to past levels of atmospheric CO2.
• at 420 ppmv Planet Earth is still close to CO2 starvation from the point of view of plant viability and productivity.
• only ~20,000 years ago, at the start of our present warm Holocene interglacial period, that the level of CO2 in the atmosphere had reached ~180 ppmv by the end of the last Ice Age.
• CO2 at 180 ppmv was only ~20% higher than the terminal level CO2 essential for plant Photosynthesis, so, very close to the level for the survival of all Life-on-Earth.
• at a CO2 level of 180 ppmv and Plant life was already under stress with limited viability, especially at higher elevations.  CO2 is a much denser gas than air and tends to accumulate at lower elevations.
• however earlier in the Phanerozoic eon, (over the last ~550 million years), atmospheric CO2 concentrations had been even higher, (~8000 ppmv), with no adverse runaway Global warming.
• when plants evolved on land, some 450 million years ago atmospheric CO2 levels were ~5000+ ppmv.
• plant life still much prefers a CO2 rich environment. That is why CO2 is added to commercial Greenhouses at a level ~1500ppmv to promote productive plant growth.
• fortunately, over the earlier years of our current warm Holocene interglacial CO2 concentration rose to ~280 ppmv:  This was probably caused by the natural outgassing of CO2 from the gradually warming Oceans.
• that ~100 ppmv increase was from the start of the Holocene Epoch and this growth in the level of CO2 predated any burning of Fossil fuels by Mankind.
• roughly half of any added CO2 released into the atmosphere is rapidly taken up by the Photosynthetic processes of plant life.
• an immediate recent Greening of the Earth is already evident: ~+15% even in the last 50 years, as confirmed by NASA.

• the massive fertilization effect of added CO2 on all plant life as is well evidenced by current increased growth of all vegetation, leaf coverage and vastly improved crop yields.
• this added productivity for all plants includes the essential crops needed to sustain the current World population of ~8 billion.
• this high population level is now sustained by significantly less arable area under cultivation than in previous times.
• a further doubling of CO2 concentration, (Equilibrium Climate Sensitivity), 420–840 ppmv would continue to increase Global Plant productivity but could only have a further ~1% or ~+0.35°C effect on Global temperature.
• a ~1% value for a further doubling of CO2 concentration to 840 ppmv accords closely with the radiation physics assessments of Wijngaarden and Happer.
• at current CO2 rates of increase this beneficial process might take ~170 years.
• at its current level of 420 ppmv, the CO2 Warming effect of CO2 is now well beyond the tipping point where the temperature contribution of increased CO2 had become marginal as its concentration approaches and exceeds 1000 ppmv:  the diminution can be seen in the long orange tail of reducing temperature increments in the diagram above.

The temperature contributions of the Methane CH4 and Nitrous Oxide N2O

Oxygen, the by-product of Photosynthesis is ~20% of the atmosphere.  The inherent Oxidation chemistry of both Methane and Nitrous Oxide means that they are continuously purged from the atmosphere leaving only minor residues, measured in parts / billion in the atmosphere.  Even at those low concentrations Methane and Nitrous Oxide still make a limited but stable combined contribution to Global temperature of ~+0.53°C.  That temperature contribution is independent of the level of Carbon Dioxide.  Climate Alarmists believe that the continuing release of CH4 and N2O will contribute massively to Global overheating as they are very powerful heating agents.  These Alarmists are in error because they do not account for the inherent chemistry of these gasses in the Oxygen rich atmosphere where they react and dissipate so they are only capable of sustaining levels measured in parts / billion by volume.  At these low concentrations their heating effect is real but limited to ~0.5°C.

• Methane is continually released with natural gas leakages, leakages from industrial processes, the processes of natural decay, and all forms of organic life:  the oxidation of Methane in air is even visible as “wil o’ the wisp” over swampy areas.
• Nitrous Oxide is continually generated by organic decay in the natural Nitrogen cycle, by the partial burning of hydrocarbon fuels and from the 8 million daily lightning strikes.
• as Methane and Nitrous Oxide both react chemically with Oxygen in the atmosphere, they are almost entirely purged:  their residual levels remain limited to a few parts / billion in the atmosphere.
• if Methane and Nitrous Oxide were not subject to rapid chemical breakdown, their continual releases would have long since accumulated to much higher levels.
• the much higher warming potentials of Methane and Nitrous Oxide are virtually negated by the extreme dilution of their residues:
  • Methane CH4 at 1,900 / 1,000,000,000 – parts per billion, warming influence is ~+0.33°C, of which a small part might be attributed to Man-made emissions. This small temperature increase is immeasurable.
  • Nitrous Oxide N2O at 53 / 1,000,000,000 – parts per billion, warming influence is ~+0.2°C, of which only ~+0.1°C, might be attributed to Man-made emissions. This small temperature increase is immeasurable.
• Nitrous Oxide is mainly destroyed in the atmosphere by the action of light in the stratosphere and otherwise by its interaction with Oxygen, leading to a long-term, stabilized contribution to warming of ~+0.2°C over the eons.
• as a result, any further Man-made or natural releases of Methane and Nitrous Oxide are immaterial.
• the consequences of Man-made Methane or Nitrous Oxide releases have been grossly misrepresented and over-emphasized by Climate Alarmists.  Such beliefs have acted as the instigator of massive costly and destructive interventions to control these irrelevant Man-made emissions.
• Man-made contributions of extra CH4 and N2O can only have minimal temperature effects that do not justify any policy actions to control their emissions to limit Global warming.
• so, all attempts the control any Man-made releases of Methane and Nitrous Oxide can only be based on fear inducing misinformation.

• this is particularly so, as limiting Nitrous Oxide emissions by reducing the use of Nitrogen based fertilizers, as is being mandated by the European Union, could lead to truly catastrophic losses of agricultural productivity worldwide.
• any limit on the use of artificial Nitrogen based fertilizers will lead to massive famine for billions of the World population.  This dire outcome has already been clearly evidenced by the disastrous attempt to return to solely “organic farming” in Sri Lanka.

Water is by far the most significant Greenhouse gas

Adding in the temperature Greenhouse effect of Water as both Water vapor and Clouds and rescaling the earlier diagram shows the comparative insignificance of the minor Greenhouse gasses when set in the overall context of the full ~33°C Greenhouse effect.

The current temperature contributions of the Minor Greenhouse gasses:  Carbon Dioxide, Methane and Nitrous oxide are roughly as follows:

• Carbon Dioxide CO2: +~1.9°C: with diminishing effectiveness.
• Methane CH4: +~0.33°C:  static
• Nitrous Oxide N2O: +~0.20°C:  static
• Water H2O: +~30°C:  variable.

Rescaling the earlier diagram and adding in the major impact of atmospheric water, stresses the relative insignificance of future CO2 concentrations and the limited but stabilized future temperature effects of Methane and Nitrous Oxide:

• as the temperature effect of any added CO2 is approaching the saturation there is no longer any risk of gross Global temperature increase arising from Man-made emissions of Carbon Dioxide.
• from now on, (CO2 >420 ppmv), there can be no rational imperative to limit Mankind’s CO2 future CO2 emissions from burning of Fossil Fuels. That restriction will do nothing to protect the World from a non-existent overheating catastrophe nor is there any rationale to pursue any of the policies to reach “Net Zero” in the Western world.
• the sole outcome would be to undermine the successful developed economies of the Western World.
• in any event, all efforts at CO2 emissions reduction now being pursued by Western economies, (only ~17% of the Global population), are rendered wholly pointless in the context of the continued burning of fossil fuels throughout the developing world: notably China, India, Indonesia, the far East and Africa.
• that major part of the World population, (~83%), considers the immediate advancement and the prosperity of their populations to be much more important than any artificial Western fear of probably beneficial global overheating in the far future.

Colder Oceans progressively re-absorb CO2 from the atmosphere

During glaciations, the cooler Oceans are capable of absorbing more CO2 from the atmosphere.  Oceanic reabsorption of CO2 has been ongoing at least for the last ~150+ million years, since the start of the Cretaceous period, when atmospheric CO2 levels were ~3000+ppmv. Oceanic marine life, especially plankton and molluscs, naturally sequester CO2 as Calcium Carbonate, to create their protective exoskeletons.  Those calcium carbonate deposits are eventually transmuted into limestone rocks, like the white cliffs of Dover, as well as marble and all the other forms of deposited limestone.

During some future 100,000-year glaciation, this inexorable natural process reabsorbing CO2 will eventually result in the termination of all Life-on-Earth as CO2 is progressively sequestered in the Oceans to be deposited as limestones, Calcium Carbonate.

The natural re-absorption of CO2 will eventually result in the atmospheric level of CO2, falling below the ~150 ppmv plant survival level.  It was only ~20,000 years ago, at the start of our Holocene inter-glacial global CO2 level was about 180 ppmv:  this was very close to that terminal threshold, when Plant Photosynthesis could no longer operate and so plants could no longer survive.  Even at the 180ppmv level much of plant life was already severely stressed, especially at higher elevations.  It is even conceivable that the by burning Fossil. Fuels and emitting some extra CO2 that Mankind could delay  by millennia the CO2 levels reaching the fatal threshold of 150 ppmv.

Conclusions

• from the current CO2 level at 420 ppmv CO2 warming potential is >85% saturated,
• the demonizing of CO2 from Western sources and the Western pursuit of “Net Zero” to prevent a Man-made global overheating catastrophe is a pointless and economically destructive “fool’s errand” for any nation that participates.  The World’s developing Nations are bound to continue to use their available fossil fuels to ensure their advancement and indeed their is no reason why they should not continue to do so.

• any attempt by Mankind to remove CO2 from the atmosphere or from the exhausts of fossil fuel burning plant is similarly misguided.
• “Carbon Capture and Storage, (CCS)” can only be characterized as “a costly and energy expensive way of throwing away irrelevant amounts of useful plant food”:  the idea could only ever have been promoted by individuals, who had carefully forgotten all their elementary Biology.

• as both Methane CH4 and Nitrous Oxide N2O are purged from the atmosphere by their inherent chemistry, the temperature effect of the residues these powerful Greenhouse gasses is also limited:  together they contribute a limited and stable total of ~0.53°C overall to the Greenhouse effect, with ~0.33°C attributable to Methane and ~0.20°C attributable to the Nitrous Oxide.
• this +~0.53°C overall temperature contribution from the residual combination of CH4 and N2O has been stable ever since Photosynthesis took hold and raised the level of Oxygen in the atmosphere over the past billion years.
• the simple fact the Methane and Nitrous Oxide are naturally purged from the atmosphere means that any Green policy ideas of controlling Livestock farming or limiting the use of Nitrogen fertilizers are pointless.  They would be destructive to the survival of current civilizations and fatal to their populations.

Never forget:

Sun Tsu’s first art of war:

“The supreme art of war is to subdue the enemy without fighting.”

That is exactly what is happening as Western governments pursue self-harming Green Energy policies.  There is no better way to damage Western societies than by rendering their energy supplies unreliable and expensive.

So Green thinking can only be regarded as a continuation of the “Cold War” intended to undermine the viability of the economies of the Western world.

Cui bono  Who Benefits ?

and

The late Professor David MacKay:

“the dependence on Weather-Dependent “Renewable Energy” to power a developed economy is an Appalling Delusion”. 

There’s so much delusion and I think it’s so dangerous for humanity that people allow themselves to have these delusions that they’re willing to not think carefully about the numbers, the realities, and the laws of physics and the realities of engineering… humanity really does need to pay attention to arithmetic, and the laws of physics.”

Arithmetic?  Laws of physics?  Engineering?  These are all lost on politicians, to our incalculable cost.

References

This short paper sets out the long-term context for the Greenhouse effect and the importance of warmth to the flourishing of all life on planet Earth.

A Brief History of Climate, From Prehistory to The Imaginary Crisis of the 21st Century

Dependence of Earth’s Thermal Radiation on Five Most Abundant Greenhouse Gases W. A. van Wijngaarden and W. Happer       https://arxiv.org/pdf/2006.03098.pdf